bfa152fa5e
Allow noflush suspend/resume of device-mapper device only for the case where the device size is unchanged. Otherwise, dm-multipath devices can stall when resumed if noflush was used when suspending them, all paths have failed and queue_if_no_path is set. Explanation: 1. Something is doing fsync() on the block dev, holding inode->i_sem 2. The fsync write is blocked by all-paths-down and queue_if_no_path 3. Someone requests to suspend the dm device with noflush. Pending writes are left in queue. 4. In the middle of dm_resume(), __bind() tries to get inode->i_sem to do __set_size() and waits forever. 'noflush suspend' is a new device-mapper feature introduced in early 2.6.20. So I hope the fix being included before 2.6.20 is released. Example of reproducer: 1. Create a multipath device by dmsetup 2. Fail all paths during mkfs 3. Do dmsetup suspend --noflush and load new map with healthy paths 4. Do dmsetup resume Signed-off-by: Jun'ichi Nomura <j-nomura@ce.jp.nec.com> Acked-by: Alasdair G Kergon <agk@redhat.com> Signed-off-by: Andrew Morton <akpm@osdl.org> Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org> |
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acorn | ||
acpi | ||
amba | ||
ata | ||
atm | ||
base | ||
block | ||
bluetooth | ||
cdrom | ||
char | ||
clocksource | ||
connector | ||
cpufreq | ||
crypto | ||
dio | ||
dma | ||
edac | ||
eisa | ||
fc4 | ||
firmware | ||
hid | ||
hwmon | ||
i2c | ||
ide | ||
ieee1394 | ||
infiniband | ||
input | ||
isdn | ||
kvm | ||
leds | ||
macintosh | ||
mca | ||
md | ||
media | ||
message | ||
mfd | ||
misc | ||
mmc | ||
mtd | ||
net | ||
nubus | ||
oprofile | ||
parisc | ||
parport | ||
pci | ||
pcmcia | ||
pnp | ||
ps3 | ||
rapidio | ||
rtc | ||
s390 | ||
sbus | ||
scsi | ||
serial | ||
sh | ||
sn | ||
spi | ||
tc | ||
telephony | ||
usb | ||
video | ||
w1 | ||
zorro | ||
Kconfig | ||
Makefile |